Plum and dates pitting equipment or apparatuses are known since more than twenty years, said equipment or apparatuses having been improved in terms of the mechanism actuating on the punch (punches) which penetrate the fruit, but said mechanism has always been based on a cam and eccentric. Said mechanisms, apart from requiring complex maintenance and being subject to wear, are unsafe per se, as they produce breakage of equipment parts which lead to extended periods for the repair thereof, with the corresponding costs. Also, such mechanisms, due to their conception, require lubrication, which may contaminate product. Even when using a food grade lubricant, foodstuff quality is reduced, as it typically can not be washed.
Many of the previous art mechanisms use spring punching heads, said springs being compressed most of the time, thus requiring power. Also, when the motor stops said springs relax suddenly, thus adding a risk factor for machine operators. Spring punching heads are also difficult to calibrate, as the synchronism to be attained between the conveyor belt and the head descending movement is so complicated that at least two individuals are necessary in order to configure same.
U.S. Pat. No. 5,619,912 discloses a pitting machine which conveyor belt is inclined as regards the horizontal plane, said machine includes a cam chamber able to rotate and which is associated to a pivot which carries out a pivoting movement in response to said cam box rotation and over which the punching head is associated. The whole assembly is positioned above the belt conveying fruits and inside the pitting machine.
U.S. Pat. No. 5,870,949 discloses a pitting machine which punching head is directly related to an eccentric which is associated to a cam, such assembly being positioned above the belt conveying fruits and inside the pitting machine. This includes a cleaning blade mounted on the machine frame, which blade loosens pits from containers as these move away from the extraction area.
Although it is desirable for the punch trajectory in pitting machines to be substantially perpendicular to the conveyor belt travel (and thence to the fruit travel), in order to provide a better extraction of pits the present invention provides a curvilinear trajectory of punch which exhibits a large curvature radius, which greatly resembles this kind of trajectory. The reason for this trajectory change is due to the novel combination of pit extraction mechanical elements employed, which confer the following advantages as regards prior art: they improve efficiency of the fruit pits extraction mechanism without requiring lubrication; they are placed outside the pitting machine, far from the fruit to be pitted; they use a spring-free punching head; they are formed with commercially available elements; pitting area is easily and safely accessed for inspection and cleaning purposes; they require low maintenance, requiring short machine shutdowns and long operating periods.